Valve apparatus

ABSTRACT

A rotating valve apparatus including a cylindrical casing, a shaft arranged symmetrically in the casing, a member fixedly attached to the shaft and in close fit with the cylindrical casing, defining separated chambers within the casing, at least one outlet fixedly arranged along the circumference of the casing and a plurality of axially arranged inlets, each of which is constantly in fluid communication with a respective one of the separated chambers. The axially arranged inlets are alternately in fluid connection with the outlet fixedly arranged along the circumference of the casing in response to rotation of the shaft and the member with respect to the casing. The member has an elliptically shaped cross section.

TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to valve apparatuses. Theinvention is preferably, but not exclusively, intended for a generatorsystem for converting thermal energy to electric energy.

DESCRIPTION OF RELATED ART AND BACKGROUND OF THE INVENTION

In known generator systems for converting thermal energy to electricenergy there is provided a magnetic circuit of a suitable magneticmaterial and a coil arranged around the magnetic circuit. Atemperature-varying arrangement varies the temperature of the magneticcircuit alternately above and below a phase transition temperature suchas the Curie point to thereby vary the reluctance of the magneticcircuit and the magnetization of the magnetic circuit is modulated bythe varying reluctance so as to induce electric energy in the coilarranged around the magnetic circuit. The temperature-varyingarrangement passes alternately hot and cold fluid by the magneticcircuit and comprises typically one or several feed pumps, piping, and avalve manifold.

JP 7107764 discloses such generator system provided with a switch valvecomprising a hot water inlet port, a cold water inlet port, and twooutlet pipes. When the switch valve rotates the outlet pipes receivealternately water from the hot water inlet port and the cold water inletport. The phase between the outlet pipes is 180°.

SUMMARY OF THE INVENTION

A problem of such arrangement is that energetically inefficient cyclingof fluid is achieved and that disturbances during fluid switching occur.

Another limitation is that the frequency of the thermal cycling islimited.

Further, the switch valve of JP 7107764 may not be optimally designedfor different kinds of thermomagnetic generator systems. The cost pernet power produced by a generator system featuring the known switchvalve may not be optimum.

It is therefore an object of the present invention to provide a valveapparatus, by which the above limitations can be overcome.

It is a particular object of the invention to provide such valveapparatus, which can provide for a smooth and energetically efficientcycling of fluid.

It is still a further object of the invention to provide such valveapparatus, which is reliable, flexible, and of reasonable cost.

It is yet a further object of the invention to provide such valveapparatus, which is optimally designed for use in a temperature-varyingarrangement for a specified kind of generator system converting thermalenergy to electric energy.

These objects, among others, are according to the present inventionattained by valve apparatuses as specified in the appended patentclaims.

According to a first aspect of the invention there is provided a valveapparatus comprising a cylindrical casing, a shaft arrangedsymmetrically in the casing, a member fixedly attached to the shaft andin close fit with the cylindrical casing, thereby defining separatedchambers within the casing, a plurality of axially arranged inlets, eachof which being constantly in fluid communication with a respective oneof the separated chambers, and at least one outlet fixedly arrangedalong the circumference of the casing, wherein the separated chambersand thereby the axially arranged inlets are alternately in fluidconnection with a circumferential reference point of the at least oneoutlet in response to rotation of the shaft and the member with respectto the casing. The member has an elliptically shaped cross section.

Preferably, the member is in close fit with the cylindrical casing inthe plane of the elliptically shaped cross section.

The member may be realized as a thin plate or as a slantingly cut solidcylinder having a diameter slightly less than the inner diameter of thecylindrical casing.

The valve apparatus of the first aspect of the invention provides forenergetically efficient cycling of fluid and disturbances during fluidswitching are minimized.

The elliptically shaped member provides for a reliable and robust valveapparatus to a reasonable cost.

According to a second aspect of the invention there is provided a valveapparatus comprising a cylindrical casing, a shaft arrangedsymmetrically in the casing, a member fixedly attached to the shaft andin close fit with the cylindrical casing, thereby defining separatedchambers within the casing, a plurality of axially arranged inlets, eachof which being constantly in fluid communication with a respective oneof the separated chambers, and at least one outlet fixedly arrangedalong the circumference of the casing, wherein the separated chambersand thereby the axially arranged inlets are alternately in fluidconnection with a circumferential reference point of the at least oneoutlet in response to rotation of the shaft and the member with respectto the casing. The number of the chambers is at least four.

Preferably, the member comprises sidewalls extending axially andradially from the shaft to the casing, and end covers extending radiallyfrom the shaft to the casing and circumferentially between neighboringones of the sidewalls. Each of the chambers is delimited by (i) two ofthe sidewalls, (ii) one of the end covers, and (iii) the cylindricalcasing.

The valve apparatus of the second aspect of the invention provides foran increased frequency of the output fluid pulses for a given rotationalspeed. Alternatively, for a maintained pulse frequency, the requirementson the rotational speed can be relaxed.

The higher number of chambers that is provided for a given rotationalspeed, the higher pulse frequency is obtained.

According to a third aspect of the invention there is provided a valveapparatus comprising a cylindrical casing, a shaft arrangedsymmetrically in the casing, a member fixedly attached to the shaft andin close fit with the cylindrical casing, thereby defining separatedchambers within the casing, a plurality of axially arranged inlets, eachof which being constantly in fluid communication with a respective oneof the separated chambers, and at least three outlets fixedly arrangedalong the circumference of the casing, wherein the separated chambersand thereby the axially arranged inlets are alternately in fluidconnection with the at least three outlets in response to rotation ofthe shaft and the member with respect to the casing. The number ofoutlets may advantageously be higher and/or an even number such as four,six, or even higher.

The valve apparatus of the third aspect of the invention provides forenergetically efficient cycling of fluid and disturbances during fluidswitching can be minimized.

A valve apparatus that has N*3 outlets, where N is a positive integer,preferably an even integer, is particularly suited to be used in athree-phase magnetothermal generator system.

According to a fourth aspect of the invention there is provided a valveapparatus comprising a cylindrical casing, a shaft arrangedsymmetrically in the casing, a member fixedly attached to the shaft andin close fit with the cylindrical casing, thereby defining separatedchambers within the casing, and a plurality of axially arranged inlets,each of which being constantly in fluid communication with a respectiveone of the separated chambers. The valve apparatus is provided with asingle outlet fixedly arranged along the circumference of the casing,wherein the separated chambers and thereby the axially arranged inletsare alternately in fluid connection with a circumferential referencepoint of the single outlet in response to rotation of the shaft and themember with respect to the casing. The single outlet may extend alongthe entire circumference of the casing or at least along a major portionthereof.

The valve apparatus of the fourth aspect of the invention provides forenergetically efficient cycling of fluid and disturbances during fluidswitching are minimized. If the single outlet has large cross sectionalarea the losses are low.

The valve apparatus may be provided with an output wherein differentportions across the cross section thereof have different fluid pathlengths so that any introduced phase delays across the cross section ofthe outlet can be compensated for. The valve apparatus is particularlysuited to be used in a single-phase magnetothermal generator system.

Embodiments of the invention are set out in the dependent claims and aredisclosed in the detailed description.

The present invention features a valve apparatus, which is simple,reliable, and robust, and by which smooth and energetically efficientpumping and distribution of fluids are enabled.

The valve apparatus of the present invention can be used for the thermalcycling of fluid in various kinds of thermomagnetic generator systems orcan be used in entirely different applications, in which fluids ofdifferent characteristics should be alternately output in a singleoutlet.

Further characteristics of the invention and advantages thereof, will beevident from the following detailed description of preferred embodimentsof the present invention given hereinafter and the accompanying FIGS.1-5, which are given by way of illustration only and thus, are notlimitative of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 display each schematically in a perspective view arotating valve apparatus according to a respective embodiment of theinvention.

FIG. 3 displays schematically in a diagrammatic view a thermomagneticgenerator system according to a further embodiment of the presentinvention.

FIG. 4 displays schematically in a cross sectional view a rotating valveapparatus according to an embodiment of the invention.

FIG. 5 displays schematically in a perspective view a rotating valveapparatus according to an embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

A rotating valve apparatus according to an embodiment of the inventionis disclosed in FIG. 1. A hollow cylinder or cylindrical casing 41houses a symmetrically arranged rotatable shaft 42, to which a member 43is fixedly attached. The member 43, which preferably is thermallyisolating, is provided in close fit with the cylindrical casing 41 anddefines a first and a second identical compartment or chamber 44 a-b ofthe apparatus. The member 43 is an elliptic disc fixedly mounted on theshaft 42 at an axial position and with an inclination angle such thateach of the outlets 46 a-f at the circumference of the cylindricalcasing 41 is alternately in fluid connection with the chambers 44 a-b asthe shaft 42 and the elliptic disc 43 are rotated with respect to thecylindrical casing 41.

The elliptic plate might be fabricated by cutting it from a solidcylinder having a diameter slightly less than the inner diameter of thecylindrical casing.

Alternatively, the member 43 has other shapes as long it provides theabove functionality and has an elliptically shaped cross section. Forinstance, the surfaces of the member 43 may be curved.

One of the chambers 44 a is constantly in fluid communication with afirst axially arranged inlet 45 a, and is configured to receive oroutput fluid of a first characteristic, and one of the chambers 44 b isconstantly in fluid communication with a second axially arranged inlet45 b, and is configured to receive or output fluid of a secondcharacteristic.

Further, a number of outlets 46 a-f is arranged circumferentially in thecasing 41, preferably with equal distances between one another. Thecircumferentially arranged outlets 46 a-f can alternately be put influid communication with the respective chambers 44 a-b by rotating theshaft 42 and the member 43, thereby also rotating the chambers 44 a-b.

The shaft 42 is advantageously mounted in the cylindrical casing 41 bymeans of bearings and means, e.g. an electric motor (not illustrated),is provided to apply a driving torque on the shaft 42. Alternatively,the rotating valve apparatus is self-propulsive in response to beingexposed to fluids flowing through the inlets of the rotating valveapparatus by means of a pump arrangement). In yet an alternative versionthe valve apparatus has an integrated impeller arrangement for thecirculation, i.e. pumping, of the fluids (in which instance any externalpump arrangement may be dispensed with). Such impeller arrangement canbe separated from the member 43 or it can be integrated with the member43 into a single-piece device by means of suitably shaping the surfacesof the member 43 in the two axial directions to resemble the operationof impellers. Such combined pump and valve apparatus is described in ourcopending European patent application No. 07120950.6 filed on 19 Nov.2007, the contents of which being hereby incorporated by reference.

During operation of the valve apparatus in a first operation mode, theshaft 42 and thereby the member 43 are steadily rotated with respect tothe casing 41 and the outlets 46 a-f, thereby sucking a fluid of a firstcharacteristic trough the first axially arranged inlet 45 a and into thefirst chamber 44 a constantly in fluid communication with the firstaxially arranged inlet 45 a, and sucking a fluid of a secondcharacteristic trough the second axially arranged inlet 45 b and intothe second chamber 44 b constantly in fluid communication with thesecond axially arranged inlet 45 b. As the member 43 and thus thechambers 44 a-b thereof are rotated with respect to the casing thefluids of the first and second characteristics are alternately outputthrough the circumferentially arranged outlets 46 a-f.

The circumferentially arranged outlets 46 a-f alternately output pulsesof fluids of the first and second characteristics. The rotational speedfor a given number of chambers controls the wavelength and frequency ofthe train of fluid pulses and the angular separation of the outletscontrols the phase shift between them.

The fluids of the first and second characteristics may be fluids, suchas e.g. water or other heat exchange fluid, of different temperatures.Alternatively, different fluids or fluids having different propertiesare mixed by the valve apparatus.

In a second operation mode the valve apparatus operates in a reciprocalmanner to divide up fluid pulses of the first and second characteristicsreceived at the circumferentially arranged outlets 46 a-f, being inletsin this operation mode. The shaft 42 and thereby the member 43 aresteadily rotated in the opposite direction with respect to the casing 41and the outlets 46 a-f. Hereby, the fluid pulses of the first and secondcharacteristic are sucked through the circumferentially arranged outlets46 a-f and alternately into the respective chambers 44 a-b of the casing41. The fluid pulses that are collected in the first chamber 44 aconstantly in fluid communication with the first axially arranged inlet45 a is output there through, and the fluid pulses that are collected inthe second chamber 44 b constantly in fluid communication with thesecond axially arranged inlet 45 b is output there through. Thus, theaxially arranged inlets 45 a-b are outlets in this operation mode. Ifthe rotational speed of the shaft 42 is adapted to the frequency of thefluid pulses and the phase shift between the fluid pulses at thecircumferentially arranged outlets 46 a-f is adapted to the angularseparation of the circumferentially arranged outlets 46 a-f, fluid ofthe first characteristic can be collected by the valve apparatus andoutput though the first axially arranged inlet 45 a and fluid of thesecond characteristic can be collected by the valve apparatus and outputthough the second axially arranged inlet 45 b.

It should be understood by a person skilled in the art that even if theapparatus is described in the present text and in the appended patentclaims as having axially arranged inlets and circumferentially arrangedoutlets, they can be operated as axially arranged outlets andcircumferentially arranged inlets as described above. Thus, the wordingused covers both operation modes.

FIG. 2 illustrates a valve apparatus, which differs from the one of FIG.1 in that only three outlets 46 a-f are arranged circumferentially inthe casing 41, preferably with equal distances between one another.

The valve apparatus of FIG. 2 can preferably be used in a three-phasethermomagnetic generator system as being illustrated in FIG. 3 in orderto provide the temperature variation above and below the phasetransition temperature of the magnetic material of the magnetic circuits1 thereof.

Three only schematically indicated magnetic circuits 1 are provided,each of which being operatively connected to a respective LC circuit 11including a winding or coil 7 and a capacitor 9 connected in parallel.Advantageously, the ratio of the resonance frequency of the resonantelectric circuit 11 and the frequency of the temperature variation aboveand below the phase transition temperature of the magnetic material isapproximately ½ or n/2, where n is a positive integer.

A temperature-varying device 5 comprises an outer part, which includes afirst external pipe arrangement 21, in which hot fluid is circulated bya feed pump 22, and a second external pipe arrangement 23, in which coldfluid is circulated by a feed pump 24. The hot and cold fluids of theouter part are entirely isolated from each other as well as from thematerial of the magnetic circuits 1.

The hot fluid in the first external pipe arrangement 21 transfers heatto fluid in a first intermediate pipe arrangement 25 via a first heatexchanger 26 and the cold fluid in the second external pipe arrangement23 transfers cold to fluid in a second intermediate pipe arrangement 27via a second heat exchanger 28. Each of the first and secondintermediate pipe arrangements 25, 27 is connected between a first oneof the valve apparatus of FIG. 2, denoted by reference numeral 29, and asecond one of the valve apparatus of FIG. 2, denoted by referencenumeral 30, to transport fluid from the first valve apparatus 29 to thesecond valve apparatus 30.

It shall be appreciated that the outer part may be exchanged for anyother kind of arrangement for transferring heat and cold in the heatexchangers 26 and 28. For instance, heat may be transferred to fluid inthe first intermediate pipe arrangement 25 in the first heat exchanger26 via an incinerator, hot sand, a solar heating panel, or similar.

Finally, a first 31, a second 32, and a third 33 internal pipearrangement are each connected between the second valve apparatus 30 andthe first valve apparatus 29 via a respective one of the magneticcircuits 1.

A single fluid is flowing in the inner part of the temperature-varyingdevice 5, which comprises the intermediate and internal pipearrangements and the first and second valve apparatuses. The inner partthus provides a closed fluid loop.

The second valve apparatus 30 is provided for alternately switching hotfluid from the first intermediate pipe arrangement 25 and cold fluidfrom the second intermediate pipe arrangement 27 into each one of thefirst, second and third internal pipe arrangements 31, 32, 33,preferably with a 120° phase shift there in between. Thus, the secondvalve apparatus “chops” the hot and cold fluids and forms trains ofalternating hot and cold fluid pulses, which are fed into each of theinternal pipe arrangements. As the hot and cold fluid pulses pass by, orthrough holes in, a magnetic material of the magnetic circuits 1, themagnetic material will be alternately heated above and cooled below thephase transition temperature.

The terms hot fluid and cold fluid as used in the description of thisand next embodiment are intended to indicate fluid having a temperatureabove the phase transition temperature of the magnetic material of theportion 3 of the magnetic circuit and fluid having a temperature belowthe phase transition temperature of the magnetic material of the portion3 of the magnetic circuit, respectively.

The variation of temperature above and below the phase transitiontemperature causes drastic changes of the permeability of the magneticmaterial and thus a rapid variation of the magnetic resistance orreluctance of the magnetic circuit 1. In other words, the magnetizationis varied rapidly when a constant magnetic field is applied.

Provided that a magnetic flux is provided in the magnetic circuit 1, therapid variation of the reluctance will modulate the magnetic flux,thereby obtaining a rapidly varying magnetic flux in the magneticcircuit 1. As a result a magnetomotive force and an alternating currentare obtained in the coil 7.

The magnetic material can be provided as parallel sheets or platespreferably arranged in parallel to one another, granulates, smallspheres, wires, fabrics or similar allowing the fluid, in a laminar orturbulent flow, to exchange heat with the magnetic material with largecontact surface.

After having passed the magnetic material the temperature variationbetween the hot and cold fluid pulses is smaller and smoother. Thetrains of hot and cold fluid pulses are then returned in the respectiveinternal pipe arrangements 31, 32, 33 to the first valve apparatus 29,which is synchronized with the trains of hot and cold fluid pulses.

The first valve apparatus 29 is thus provided for alternately switchingthe hotter fluid pulses from the first, second and third internal pipearrangements 31, 32, 33 into the first intermediate pipe arrangement 25and the colder fluid pulses from the first, second and third internalpipe arrangements 31, 32, 33 into the second intermediate pipearrangement 27. Hereby, the hotter and colder fluid pulses are returnedto the respective intermediate pipe arrangement, from which they wereoriginating. The fluid in the first intermediate pipe arrangement 25 isthen returned to the first heat exchanger 26 in order to be heated againand the fluid in the second intermediate pipe arrangement 27 is thenreturned to the second heat exchanger 28 in order to be cooled again.

The fluid in the inner part is driven in a single direction by feedpumps 34, 35.

The rotating valves 29, 30 of FIG. 2 are advantageously mounted on asingle shaft to be rotated simultaneously/synchronously with a suitablephase shift there in between.

In an alternative embodiment the first valve apparatus 29, particularlywhere the temperature difference between the hotter and colder fluidpulses is low, the hotter and colder fluid pulses from the first, secondand third internal pipe arrangements may not have to be switched backinto the second and first intermediate pipe arrangements. Thus, thefirst valve apparatus 29 may be dispensed with and another kind ofpassive distribution or mixing arrangement may be used instead in orderto return the fluids to the second and first intermediate pipearrangement. If an open circuit is used the fluids do not have to bereturned.

The three-phase generator system of FIG. 3 comprises furtheradvantageously a power conversion device connected to the capacitors 9of the three generator units or phases at the output. The coils 7 andthe power conversion device are controlled to match the cycle of thethermal variation and to thereby enable optimum energy to be tapped fromthe circuit. The power conversion device may comprise an AC/DC or AC/ACfrequency converter or a power electronic converter including a currentor voltage source converter 36, which encompasses a rectifier and aninverter at the DC side of the rectifier.

Additionally, or alternatively, a battery is connected at the DC side.This is particularly advantageous if the power output from the generatoris very fluctuating.

A transformer 37 is connected to the output of the voltage sourceconverter 36 to transform the output voltage and frequency of about 1 kVand 1 Hz from the multiphase generator to a frequency and a voltage (50Hz, 10 kV) suitable for normal grid connection. The rating of theequipment is typically larger than 1 kW.

Preferably, the generator system of the present invention is providedfor electric power generation in the range of 100 kW to 50 MW, and morepreferably in the range of 1-5 MW. Several generator systems may bearranged together as modules to generate electric powers of about 10-50MW.

Further details regarding magnetothermal generator systems in which therotating valve apparatus of the present invention can be implemented arefound in our copending Swedish patent applications Nos. 0700779-2,0700780-0, and 0700781-8 filed on Mar. 28, 2007, the contents of whichbeing hereby incorporated by reference.

It shall be appreciated that for a three-phase generator system thevalve apparatus may comprise 3*N outlets fixedly arranged along thecircumference of the casing of the valve apparatus, where N is aninteger, preferably an even integer.

If a single-phase thermomagnetic generator system including a rotatingvalve apparatus of the present invention should be provided, therotating valve apparatus can preferably be provided with a singleoutput.

FIG. 4 displays schematically such a rotating valve apparatus.

The rotating valve apparatus is similar to the ones displayed in FIGS. 1and 2, but has a single outlet 71, which extends around the entirecircumference of the rotating valve apparatus. The single outlet 71includes eight sub-outlets 72, which are laterally separated portions ofthe single outlet 71. The sub-outlets 72 may be separated by fluidguiding walls (not illustrated). The cold fluid pulses are white and thehot fluid pulses are grey.

The single outlet 71 is preferably designed with phase delayedsub-outlets 72 as realized through tailor suited fluid paths. The singleoutlet 71 has preferably a fluid path length that varies along thecircumference of the casing of the rotating valve apparatus depending onthe rotational speed of the shaft and the member such that theinterfaces between fluids originating from different ones of the axiallyarranged inlets will be essentially vertical to the flow direction ofthe fluids in a downstream end of the single outlet 71 as beingillustrated in FIG. 4. In other words, the fluid pulses in the differentsub-outlets 72 are in phase with one another.

A rotating valve apparatus according to a further embodiment of theinvention is disclosed in FIG. 5. A hollow cylinder or cylindricalcasing 41 houses a symmetrically arranged rotatable shaft 42, to which amember 43 is fixedly attached. The member 43, which preferably isthermally isolating, is provided in close fit with the cylindricalcasing 41 and defines four essentially separated and identicalcompartments or chambers 44 a-d of the apparatus. Each of the chambers44 a-d is defined by (i) two sidewalls that extend axially and radiallyfrom the shaft 42 to the casing 1, (ii) an end cover that extendsradially from the shaft 42 to the casing 1 and circumferentially betweenthe two sidewalls, and (iii) the casing 1. Two of the chambers 44 a, 44c are constantly in fluid communication with a first axially arrangedinlet 45 a, and is configured to receive or output fluid of a firstcharacteristic, and two of the chambers 44 b, 44 d are constantly influid communication with a second axially arranged inlet 45 b, and isconfigured to receive or output fluid of a second characteristic.

Further, a number of outlets 46 a-f is arranged circumferentially in thecasing 41, preferably with equal distances between one another. Thecircumferentially arranged outlets 46 a-f can alternately be put influid communication with the respective chambers 44 a-d by rotating theshaft 42 and the member 43, thereby also rotating the chambers 44 a-d.

The shaft 42 is advantageously mounted in the cylindrical casing 41 bymeans of bearings and means, e.g. an electric motor (not illustrated),is provided to apply a driving torque on the shaft 42. Alternatively,the rotating valve apparatus is self-propulsive in response to beingexposed to fluids flowing through the inlets of the rotating valveapparatus by means of a pump arrangement). In yet an alternative versionthe valve device has an integrated impeller arrangement for thecirculation, i.e. pumping, of the fluids (in which instance any externalpump arrangement may be dispensed with). Such impeller arrangement canbe separated from the member 43 or it can be integrated with the member43 into a single-piece device by means of suitably shaping the surfacesof the member 43 in the two axial directions to resemble the operationof impellers. Such combined pump and valve apparatus is described in ourcopending European patent application No. 07120950.6 filed on 19 Nov.2007, the contents of which being hereby incorporated by reference.

During operation of the valve apparatus in a first operation mode, theshaft 42 and thereby the member 43 are steadily rotated with respect tothe casing 41 and the outlets 46 a-f, thereby sucking a fluid of a firstcharacteristic trough the first axially arranged inlet 45 a and into thetwo chambers 44 a, 44 c constantly in fluid communication with the firstaxially arranged inlet 45 a, and sucking a fluid of a secondcharacteristic trough the second axially arranged inlet 45 b and intothe two chambers 44 b, 44 d constantly in fluid communication with thesecond axially arranged inlet 45 b. As the member 43 and thus thechambers 44 a-d thereof are rotated with respect to the casing thefluids of the first and second characteristics are alternately outputthrough the circumferentially arranged outlets 46 a-f.

The circumferentially arranged outlets 46 a-f alternately output pulsesof fluids of the first and second characteristics. The rotational speedfor a given number of chambers controls the wavelength and frequency ofthe train of fluid pulses and the angular separation of the outletscontrols the phase shift between them.

The fluids of the first and second characteristics may be fluids, suchas e.g. water or other heat exchange fluid, of different temperatures.Alternatively, different fluids or fluids having different propertiesare mixed by the valve apparatus.

In a second operation mode the valve apparatus operates in a reciprocalmanner to divide up fluid pulses of the first and second characteristicsreceived at the circumferentially arranged outlets 46 a-f, being inletsin this operation mode. The shaft 42 and thereby the member 43 aresteadily rotated in the opposite direction with respect to the casing 41and the outlets 46 a-f. Hereby, the fluid pulses of the first and secondcharacteristic are sucked through the circumferentially arranged outlets46 a-f and alternately into the respective chambers 44 a-d of the casing41. The fluid pulses that are collected in the two chambers 44 a, 44 cconstantly in fluid communication with the first axially arranged inlet45 a is output there through, and the fluid pulses that are collected inthe two chambers 44 b, 44 d constantly in fluid communication with thesecond axially arranged inlet 45 b is output there through. Thus, theaxially arranged inlets 45 a-b are outlets in this operation mode. Ifthe rotational speed of the shaft 42 is adapted to the frequency of thefluid pulses and the phase shift between the fluid pulses at thecircumferentially arranged outlets 46 a-f is adapted to the angularseparation of the circumferentially arranged outlets 46 a-f, fluid ofthe first characteristic can be collected by the valve apparatus andoutput though the first axially arranged inlet 45 a and fluid of thesecond characteristic can be collected by the valve apparatus and outputthough the second axially arranged inlet 45 b.

While the rotating valve apparatus of FIG. 5 has four separatedchambers, the invention is not limited in this respect. There may beprovided more than four separated chambers, such as six or eightchambers, in order to increase the frequency of the fluid pulses.

In the valve apparatuses of the present invention, a small separationbetween the chamber-dividing and rotating member and the wall of thecylindrical casing may advantageously be allowed, reducing oreliminating solid-to-solid contact forces with only negligible amountsof fluid being mixed.

The rotating valve apparatuses are capable of distributing industrialscale amounts of fluids with different characteristics to a commonoutlet (or several common outlets) with minimal mixing on a sub-secondscale. The valve apparatus allows for a steady fluid flow with minimaldisturbance from switching, minimal switching power demand, and a longlifetime with the ability to switch millions of cycles. Conventionalvalve arrangements either are too slow, too disruptive (flow stop,pressure waves), power demanding and/or wear out after rather short anumber of cycles.

The rotating valve apparatus is applicable for industrial processeswhich involve alternating distribution of fluid with differentcharacteristics into a common outlet, keeping the fluids separated withminimal mixing at a rate of a few cycles per second, continuously fore.g. several years. The fluids have preferably roughly similar fluidproperties concerning e.g. density, viscosity, etc. They may consist ofdifferent substances, like water and ethanol, or of the same substancein different property states, like hot and cold water or other heatexchange fluid.

1. A valve apparatus, comprising: a cylindrical casing; a shaft arrangedsymmetrically in said casing; a member fixedly attached to said shaftand in close fit with said cylindrical casing, thereby definingseparated chambers within the casing; a plurality of axially arrangedinlets, each of which being constantly in fluid communication with arespective one of said separated chambers; and at least one outletfixedly arranged along the circumference of said casing, wherein theseparated chambers and thereby the axially arranged inlets arealternately in fluid connection with a circumferential reference pointof said at least one outlet in response to rotation of said shaft andsaid member with respect to said casing, and wherein said member has anelliptically shaped cross section.
 2. The valve apparatus according toclaim 1, wherein said member is in close fit with said cylindricalcasing in the plane of said elliptically shaped cross section.
 3. Thevalve apparatus according to claim 1, wherein said member is a plate. 4.The valve apparatus according to claim 1, wherein said member is aslantingly cut solid cylinder having a diameter slightly less than theinner diameter of the cylindrical casing.
 5. The valve apparatusaccording to claim 1, wherein the valve apparatus comprises a pluralityof outlets fixedly arranged along the circumference of said casing. 6.The valve apparatus according to claim 5, wherein said plurality is atleast three, preferably at least four, and more preferably at least six.7. The valve apparatus according to claim 1, wherein the valve apparatuscomprises a single outlet fixedly arranged along the circumference ofsaid casing.
 8. A generator system for converting thermal energy toelectric energy, comprising: the valve apparatus according to claim 1.9. The generator system according to claim 8, wherein the generatorsystem is a three-phase generator system; and the valve apparatuscomprises 3*N outlets fixedly arranged along the circumference of saidcasing, where N is an integer, preferably an even integer.
 10. Thegenerator system according to claim 8, wherein the generator system is asingle-phase generator system; and the valve apparatus comprises asingle outlet fixedly arranged along the circumference of said casing.11. An electric power plant, comprising: the generator system accordingto claim
 8. 12. Use of the apparatus according to claim 1 in a method orsystem for producing electric power.
 13. A valve apparatus, comprising:a cylindrical casing; a shaft arranged symmetrically in said casing; amember fixedly attached to said shaft and in close fit with saidcylindrical casing, thereby defining separated chambers within thecasing; a plurality of axially arranged inlets, each of which beingconstantly in fluid communication with a respective one of saidseparated chambers; and at least one outlet fixedly arranged along thecircumference of said casing, wherein the separated chambers and therebythe axially arranged inlets are alternately in fluid connection with acircumferential reference point of said at least one outlet in responseto rotation of said shaft and said member with respect to said casing,and wherein the number of said chambers is at least four.
 14. The valveapparatus according to claim 13, wherein said member comprises sidewallsextending axially and radially from the shaft to the casing, and endcovers extending radially from the shaft to the casing andcircumferentially between neighboring ones of said sidewalls; and eachof the chambers is delimited by two of said sidewalls, one of said endcovers, and said cylindrical casing.
 15. A valve apparatus, comprising:a cylindrical casing; a shaft arranged symmetrically in said casing; amember fixedly attached to said shaft and in close fit with saidcylindrical casing, thereby defining separated chambers within thecasing; a plurality of axially arranged inlets, each of which beingconstantly in fluid communication with a respective one of saidseparated chambers; and a plurality of outlets fixedly arranged alongthe circumference of said casing, wherein the separated chambers andthereby the axially arranged inlets are alternately in fluid connectionwith said plurality of outlets in response to rotation of said shaft andsaid member with respect to said casing, and wherein the number of saidplurality of outlets fixedly arranged along the circumference of saidcasing is at least three.
 16. The valve apparatus according to claim 15,wherein the number of said plurality of outlets fixedly arranged alongthe circumference of said casing is at least six.
 17. A generator systemfor converting thermal energy to electric energy, comprising: the valveapparatus according to claim
 13. 18. The generator system according toclaim 17, wherein the generator system is a three-phase generatorsystem; and the valve apparatus comprises 3*N outlets fixedly arrangedalong the circumference of said casing, where N is an integer,preferably an even integer.
 19. Use of the apparatus according to claim13 in a method or system for producing electric power.
 20. A valveapparatus, comprising: a cylindrical casing; a shaft arrangedsymmetrically in said casing; a member fixedly attached to said shaftand in close fit with said cylindrical casing, thereby definingseparated chambers within the casing; and a plurality of axiallyarranged inlets, each of which being constantly in fluid communicationwith a respective one of said separated chambers, wherein said valveapparatus comprises a single outlet fixedly arranged along thecircumference of said casing, and wherein he separated chambers andthereby the axially arranged inlets are alternately in fluid connectionwith a circumferential reference point of said single outlet in responseto rotation of said shaft and said member with respect to said casing.21. The valve apparatus according to claim 20, wherein said singleoutlet extends along a major part of the circumference of said casing.22. A single-phase generator system for converting thermal energy toelectric energy, comprising: the valve apparatus according to claim 20.23. Use of the apparatus according to claim 20 in a method or system forproducing electric power.
 24. An arrangement, comprising: at least twoof the valve apparatus according to claim 1, wherein the members of theat least two valve apparatuses are fixedly attached to a single shaftand are adapted to be rotated simultaneously, optionally with a selectedphase shift there in between.
 25. A method for producing electric power,the method comprising: providing a generator comprising a valvecomprising a cylindrical casing, a shaft arranged symmetrically in saidcasing, a member fixedly attached to said shaft and in close fit withsaid cylindrical casing, thereby defining separated chambers within thecasing, a plurality of axially arranged inlets, each of which beingconstantly in fluid communication with a respective one of saidseparated chambers, and at least one outlet fixedly arranged along thecircumference of said casing, wherein the separated chambers and therebythe axially arranged inlets are alternately in fluid connection with acircumferential reference point of said at least one outlet in responseto rotation of said shaft and said member with respect to said casing,and wherein said member has an elliptically shaped cross section; andgenerating electric power with the generator.